Mail chute lock



Feb. 9, 1954 G. A. ,'BRnncslm/luv4 2,658,434

i, MAIL. CHUTE Loox Filed April l5, 1951 2 ShBetS-Shee l .By g A warn@Feb. 9, 1954 G. A.`BR|DGMAN 2,663,434

MAIL CHUTE Locx Filed April 3, 1951 2 Sheets-Sheet 2 Patented Feb. 9,1954 UNITED STATES .PATENT OFFICE MAIL CHUTE LOCK George A. Bridgman,Rochester, N. Y., assigner to Cutler Mailr Chute Company, Rochester, N.Y., a corporation of New York Application 3, 1951, Serial No. 219,010

3 Claims. 1 Y

The present invention relates to mail chutes and more particularly tolocks therefor that insure them against tampering and again-st access byother than Government agents and `persons authorized by them to `cleanand repair the .chute and maintain it generally in good working order.

Mail chutes are commonly built in sections, one to a floor of thebuilding, and each with an intermediate letter opening or mail droparranged at a convenient height. The chute proper or `conveying channelis continuous as to 'its rear and side walls, being solidly securedagainst the building wall usually by means of blind headed bolts. Thefront, however, is displaceable to give access to the interior fromfloor to ceiling for the purposes rst above mentioned and also todislodge clogs of mail matter that occasionally occur. Also, to quicklymake apparent the existence of such a clog, the front is madetransparent and, in each floor section embodies upper and lowerremovable glass panels. The top -of the upper panel slidably interlocksvertically with the ceiling structure and the bottom of the lower panelsimilarly interlocks with a base at or near the iioor. The centraladjacent vends of the two come to near abutment within a xed wallbracket frame to which the main chute channel is secured and spanningthe front of this frame and cooperating therewith to conceal, restrain,and confine these panel ends in fixed position `is a displaceablelocking bar that thus' controls the whole fioor section. It is thislocking bar with which the present invention is concerned.

The invention has for its general object to provide a locking bar ofthis .character that will be simple, convenient to handle and secure inits functioning.

A further object is to provide a key controlled locking bar that isremovable from and replaceable to its operative or locking position butcan not be carelessly left unlocked when the key is withdrawn.

Another object of the invention is to provide means for activelyejecting the bar from such seemingly attached position when it is not,in fact, locked securely in that position.

'These and other desirable objects .may he attained in the mannerdisclosed as an illustrative embodiment of the invention in thefollowing description and in the accompanying drawings forming a parthereof, in which:

Fig. 1 is a front elevation of a complete floor section of a mail chuteprovided with a locking bar constructed in accordance with andillustrating one embodiment of the presen-t invention;

Fig. 2 is a fragmentary, enlarged vertical .section taken transverselythrough the bar and contiguous parts Aon the line 2-.2 of Fig. 1;

Fig. 3 is a horizontal enlarged section through the main chute channeland upper front panel on the line 3-3 of Fig. 2;

Fig. 4 is a similar section on the same line through the panel alone aswhen removed;

Fig. 5 is an end or top plan view of the lower clement of the section.and the `locking bar including the main chute channel and its panel, thecorresponding upper parts being removed and certain details being shownin broken, horizontal section;

Fig. 6 is a horizontal central section, partly broken away, of thelocking bar taken on the line 6 6 of Fig. l on the scale of Figs. 2 and5;

Fig. 7 is a rear elevation, partly broken away, of the locking bar andon the same scale; and

Fig. 8 is a fragmentary rear View of the locking bar body showing thereceiving opening therein for the lock barrel.

The same reference numerals throughout the several views indicate thesame parts.

Referring more particularly to the drawings, W indicates the finishedwall of the building in which the chute is erected. Imbedded therein tocome flush with the surface thereof are a pair of vertically disposedangle beams I0 and at an intermediate point between floor and ceilingthere is secured to these angles by bolts I2 a rectangular supportingframe I4. A lower vertically disposed sheet metal chute channel I6 fitsclosely within this frame at its upper end which latter terminates shortof the upper edge of the frame and is riveted thereto on back and sidesas indicated at I8. The channel is thus supported in suspension, itslower end cooperating in continuation with a suitable between-licorsection including a base I9. It is open at the front and a shortdistance back from the front edge 2l) of each side wall the sheetmaterial thereof is doubled into a crimp to provide two inwardlyprojecting shoulders 22 (Fig. 3). These form seats for the rearwardsupport of the removable front panel the body of which consists of aheavy plate of glass 2li. The glass is paneled in a frame comprisinghollow sheet metal side mold-- ings 26 and connecting rails 28 at topand bottom. The latter is not shown but is identical.

The upper chute .element 3D is substantially ofv the same formation asthe lower element i6 and similarly disposed except that its lower end,with in bracket frame I4, is tapered slightly so that it wedges into thethroat of lower channel N,

as shown in Fig. 2 and covers the upper edge of the latter to form aperfect letter shed. The upper end cooperates suitably in continuationwith a between-oor installation at the ceiling including a ceiling piece32. It is closed at the front by another separate and removable panel 34embodying as before side moldings 36 and end cross rails 38. The top endof this upper panel is thrust upwardly into the ceiling piece 32 withwhich it interlocks against outward movement while the rail 38 at thelower end rests upon a forward cross bar 40 that constitutes the frontof the rigid rectangular frame I4. The rear face of this cross bar isinclined downwardly and rearwardly toward the interior of the chute asindicated at 42 to prevent descending letters from engaging the upperedge of the panel 24 and to completely insure this shedding protectionbosses 44 are added at the ends to overhang the side moldings 26 whichproject farthest into the chute and also the shoulder seats 22 withwhich they make contact. The lower rail 38 of the upper panel rests uponthe bar. The upper rail 22 of the lower panel is positioned just beneaththe bar.

It will thus be seen that, with the upper end of the upper panelslidably interlocked behind the ceiling piece 32 and the lower end ofthe lower panel similarly interlocked with the base piece I9 and bothabutting the cross rail 40 against any vertical movement while they arein their seats 22, both panels may be made secure against removalthrough forward tilting of their adjacent ends. For this purpose thereis provided a removable and replaceable locking bar 48 which masters thesituation. In the present embodiment it is pressed from heavy sheetmetal to provide a hollow body having rearwardly turned marginal flangesall around. lllhe end flanges 53 and adjacent portions of the top andbottom flanges 52 fit over reduced portions 54 (Fig. 5) on forwardextensions of the side walls of bracket frame I4 which reductions (indotted lines) provide shoulders 56 against which the edges of theflanges neatly abut. When the locking bar is so in place, thelongitudinal flanges 52 engage over and under the cross rails 38 and 28,respectively, of the upper and lower panels which rails are made wide toproject into the locking bar for this purpose.

At the center of the bar is an opening 53 (Fig.

8) which is occupied by the threaded barrel 5B r of a Yale type rotarylock 62 secured on the inside by a nut ring 64. The cylinder 66 of thislock projects rearwardly beyond the barrel and terminates in an undercutcircular head 6B opposite edges of which are machined off into ilat,parallel faces 10. When the key 'I2 fitting cylinder 66 is turned rightto an extreme stopped position as in Fig. 6, these flat faces 'I0 arevertically disposed and may pass closely between two spaced fixed lugs14 and 'I6 projecting forwardly from cross bar 40 of frame I4 whichoccurs when the unlocked locking bar is applied to the chute panels.When the key is subsequently turned left 90 (which is its limit ofmovement, Fig. 5) the head 68 rotates with the cylinder and locks behindtwo shoulders 18 on the respective lugs 14 and 16, and the panels aremade secure against forward movement and removal.

The barrel 60 cannot be unscrewed from the interiorly arranged nut ring64 because it is provided with a fiat face 80 fitting a correspondingirregularity 82 in the opening 58 provided for it in the locking bar asappears in Fig. 8.

The tumbler pins in the lock cylinder are so arranged thai'l `.when thekey is in the unlocked position of Fig. 6 it cannot be withdrawn whichis common practice in such locks and prevents the operator from leavingthe chute with the key in his possession but with the device unlocked.In the practice of the present invention, however, means are alsoprovided to prevent the operator from applying the locking bar withoutlocking it and departing with the key forgetfully left in the lock also.This provision at the same time tends to keep the key and locking bartogether when they are detached from the chute.

To these ends, the lock barrel 60 also passes through a plate 84 fittingclosely within the rear open side of the locking bar 48 and held down bythe nut'ring 64. Extending rearwardly from one end thereof is a iiange8B which, in turn, is flanged again to form a table parallel with theplate and locking bar. A leaf spring 92 is fixed to this table as byscrew 34 to project normally toward the lock cylinder 66 in the plane ofthe head 6B thereof. Its squared end comes opposite and in closeproximity to a fiat face l0 of the head as shown in Figs. 6 and 7 andwhen, as there, the cylinder is unlocked and the key cannot immediatelybe withdrawn or fall out, this spring 92 must be flexed and displacedinwardly or outwardly out of the plane of cylinder head 68 before thekey may be turned to locking position and withdrawn. This requires avoluntary eort when the whole locking device is detached from the chuteand perhaps laid aside and the key and locking bar will otherwise remaintogether.

But when the locking bar with the parts in the unlocked position ofFigs. 6 and 'I is applied to the chute in the manner previouslydescribed, lug 'I4 on the cross bar of the bracket frame is in positionto depress the spring 92 as shown in Fig. 5 and hence it isautomatically released to permit the normal rotation of the lockcylinder and the locking function set forth.

In addition to this, when the locking bar is so applied to the chuteframe, if the key is not turned to locking position to complete theoperation, the spring 92 is suiciently strong to forcibly eject thelocking bar and when the pressure of the operators hand is withdrawn itwill fall to the floor reminding him of the unsafe condition and thefact that he has left the key inthe lock.

It is seen from the foregoing disclosure that the above mentionedobjects of the invention are well fulfilled. It is to be understood thatthe foregoing disclosure is given by way of illustrative example only,rather than by way of limitation, and that Without departing from theinvention, the details may be varied within the scope of the appendedclaims.

What is claimed is:

1. A locking device for the removable front panels of mail chutesembodying a bracket frame adapted to embrace and support the channelmembers of a chute section, a removable and replaceable locking barspanning said frame and interlocking at its ends with forward portionsvof side walls thereof, a key controlled lock carried by the locking barand operatively cooperating with a portion of the frame when its key isturned in one direction to secure the bar thereto and confine saidpanels within the frame and against the channel members, means normallytending to eject the locking bar from such the bar and having a, locknut on the inside thereof and a rotary cylinder in the barrel ter-'minating in an inner head; the bracket frame turned to lockingposition; an angular post on y the rear of the locking bar including abase secured beneath the barrel locking nut, anda leaf spring on thepost in position to be depressed and tensioned by the lug and toconstitute the ejecting means when the locking bar is adjusted tolocking position on the frame.

2. A locking device for the removable front panels of mail chutes inaccordance with claim 1 in which the leaf spring is also positioned tonormally block rotation of the cylinder to locked position when thelocking bar is separated from the bracket frame.

3. A mail chute including a xed frame member, a removable panel, aretaining bar for securing said removable panel in fixed position onsaid frame member, a key operated lock mounted on said retaining bar andeffective When in normal locked position to retain said bar in xedposition on said frame member to retain said panel in the xed frame, andspring means mounted on said retaining bar and cooperating with bothsaid frame member and said lock, said spring means when in normaluntensioned condition serving to prevent turning of said lock by itskey, said spring means being tensioned by contact with said frame whensaid retaining bar is placed in normal position on said frame member topermit turning of the lock by its key.

GEORGEA. BRIDGMAN.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,232,058 Linton July 3, 1917 1,338,975 Cook May 4, 19202,042,500 Bridgman June 2, 1936 2,196,049 Andres Apr. 2, 1940 2,238,835Tveten Apr. 15, 1941 2,287,175 Heyer June 23, 1942

